In an ad that attempts to distill the GOP narrative that Warren, a Harvard Law School professor, is an elitist detached from the needs of regular working people, a narrator zings Warren for saying she created “much of the intellectual foundation” for the Occupy Wall Street movement.

A female narrator says to ominous music, “14 million Americans out of work, but instead of focusing on jobs, Elizabeth Warren sides with extreme-left protests.” A picture of Warren appears on the screen next to footage of anti-Wall Street protesters, including two seconds of a red banner that reads in part “socialist alternative.” It’s a not-so-subtle visual cue for how Crossroads would like voters to interpret Warren.

“At Occupy Wall Street, protesters attack police, do drugs and trash public parks. They support radical redistribution of wealth and violence,” the narrator says. “But Warren boasts, ‘I created much of the intellectual foundation for what they do. … I support what they do.’”

The narrative Republicans hope to crystallize in the minds of a key block of independent, blue-collar Bay State voters is that Warren is not like them and doesn’t understand them.

The ad does not mention GOP Sen. Scott Brown, who has campaigned against Warren using similar themes.

On the stump, Warren emphasizes that she “grew up on the ragged edge of the middle class” and has worked her whole life to stand up for working families.

The battle of those two narratives may well decide who comes out ahead in a hotly contested tossup race.

The ad, titled “Foundation,” will air for two weeks on broadcast stations and cable in the Boston, Springfield-Holyoke and Providence, R.I., markets. The size of the buy is $596,000.

Warren’s newly hired campaign manager, Mindy Myers, sent out a blast email to supporters Wednesday night when word of the Crossroads ad leaked.

“We don’t know what the attacks are yet, or exactly how big they’ll be. But we do know we’re going to need your help, starting tonight, to fight back and set the record straight — by telling your friends the truth about Elizabeth, by encouraging more people to stand with us, and by helping us get Elizabeth’s message out to the people of Massachusetts,” Myers wrote.